1. Field of the Invention
This invention relates to a particular air bag system. Furthermore, the invention relates to a particular air bag system manufacturing process as well as to a particular triggering process for an air bag system. Finally, a motor vehicle having at least one air bag system also forms part of the invention.
The invention basically comprises, among other elements, side air bags and roof air bags in an automobile and their housings.
2. Description of Related Art
European Patent Document EP 97 102 307.2 discloses a side impact protection device for vehicle occupants in which an air bag, in the folded ready condition, is arranged behind a covering part on the roof frame of a vehicle. This is a head gas bag which, while folded in an elongated manner, is situated behind the covering part as long as it is not triggered. In this case, a gas generator is integrated directly in the gas bag and extends maximally along one third of the gas bag. It is a disadvantage in this case that the mounting site of the gas generator is limited. Specifically, if the mounting site is situated in a forward or rearward end area of the gas bag, then an unfavorable inflation performance of the gas bag may result, which may cause the gas bag to reach its inflated condition incompletely or too late.
This can be avoided by means of an air bag according to German Patent Document DE 196 42 964.1. This air bag system for a motor vehicle contains an air bag consisting of an inflatable gas cushion, a gas generator for filling the air bag, a gas guiding tube which extends through a partitioned-off area of the air bag and has blow-out openings, a profile strip with a discharge duct constructed therein, in which the air bag, folded in a stack shape, is accommodated, and fastening elements for holding the constructional unit consisting of the profile strip, the air bag and the gas guiding tube. Although, by way of its blow-out openings, the gas guiding tube permits a targeted filling of the air bag when the air bag is triggered, the gas guiding tube and its mounting cause additional expenditures which make the whole air bag system significantly more expensive.
It is therefore an object of the present invention to provide an air bag system in which the air bag can be inflated in a targeted manner without significant additional expenditures.
This object is achieved by way of the particularly claimed air bag system, the particularly claimed air bag system manufacturing process, the particularly claimed triggering process for an air bag system and a motor vehicle as particularly claimed.
Another problem existing in the prior art is known, for example, from two older German Patent Applications DE 196 04 055.8 and DE 196 32 222.7 by the same applicant as that of the present application. This problem relates to the fastening of the air bag system on a vehicle roof with an integrated sliding roof. A remedy for this problem is provided by the present invention.
Preferred and advantageous further developments of individual implementations of the invention will also be apparent.
Without limitation, the present invention comprises, in addition to the preferred embodiments indicated in the description and the characteristics and combinations of characteristics indicated in the claims, all concepts, principles and generalizations which a person skilled in the art can easily recognize. Also, the complete contents of German Patent Applications DE 196 04 055.8 and DE 196 32 222.7, European Patent Document EP 97 102 307.2, and German Patent Document DE 196 42 964.1 are incorporated by reference into this application and become part of the disclosure content of this document.
As a result of the invention, an air bag system is provided for accommodation behind a vehicle covering. The air bag system contains an air bag which, when the air bag system is triggered, advances into a main inflating direction, and a gas generator for supplying the air bag with pressure gas during triggering of the air bag system. The gas generator and the air bag are connected by a gas distributing duct which extends at least partially at an angle with respect to the main inflating direction of the air bag. In this case, the invention provides that the gas distributing duct is formed of the air bag material.
According to the invention, the gas distributing duct, which provides an optimal distribution of the pressure gas from the gas generator and therefore an optimal inflating performance of the air bag, is formed directly of the air bag material. Thus, in contrast to the gas guiding duct of the prior art, no additional parts are required for forming the gas distributing duct. The labor expenditures for manufacturing the gas distributing duct are also not considerable since the gas distributing duct can be constructed directly while manufacturing the air bag in one work step which, as a rule, can take place simultaneously with other machining operations during manufacture of the air bag.
The gas distributing duct preferably extends at least essentially transversely to the main inflating direction of the air bag.
Although the gas distributing duct can also be mounted on the air bag, it is advantageous and therefore preferred for the gas distributing duct to be constructed integrally with the air bag. As a result, the whole air bag, together with the integrated gas distributing duct, can be manufactured in one operation from the air bag material.
In order to achieve a sufficiently stable gas distributing duct, the gas distributing duct is preferably formed by a two-layer or multi-layer air bag material. This may be further developed by forming the two-layer or multi-layer air bag material of the gas distributing duct by foldings of the air bag material. Such foldings can be implemented directly in the continuous machining and manufacturing process.
Preferably, the gas distributing duct is formed by welded connections, glued connections, sewn connections or woven connections of two or more layers of air bag material, and gas passage openings are left between the welded connections, glued connections, sewn connections or woven connections.
Additional stabilizations in possible critical areas of the gas distributing duct which are highly stressed by the flowing pressure gas may advantageously be achieved by inserted reinforcements. In particular, reinforcements may be placed in the gas distributing duct in the area of the inflow opening of pressure gas from the gas generator and/or in areas in which the gas distributing duct has a curved course.
For the accommodation of at least the air bag of the air bag system according to the invention, a suitable space is already made available by a vehicle covering, such as an inside lining and, particularly, a roof lining of a vehicle. In order to ensure that the air bag will not be loose in this space, covering and fastening devices are preferably contained so that the folded air bag can be accommodated in its ready position. Preferred covering and fastening devices contain at least one layer of a nonwoven material or paper by which the folded air bag can be accommodated in its ready position. In particular, materials and constructions are used for the covering and fastening devices which cause no noise such as squeaking. Furthermore, it is preferred to have the covering and fastening devices fixedly connected with the air bag and/or the vehicle covering. Preferably, the covering and fastening devices are glued to the air bag and/or the vehicle covering. This permits a premounting of the air bag or of the whole air bag system on a vehicle covering such as that on a vehicle ceiling.
When fastening elements used for the simultaneous fastening of the vehicle covering and the air bag system, or at least the air bag, on other vehicle parts are provided, an easy mounting with a minimal number of parts is permitted if the air bag or the air bag system is not premounted on the vehicle covering, as described above. Also, with premounted units consisting of the vehicle covering and the air bag or air bag system according to the above description, a particularly stable fastening of such constructional units on vehicle parts is achieved, since the air bag or the air bag system are included in the fastening.
In a particularly advantageous manner, the gas distributing duct may be arranged on the side of the air bag which advances during the triggering of the air bag system and appears first from behind the vehicle covering. As a result of this further development, the first inflating of the gas distributing duct during triggering of the air bag system can be utilized for opening-up the vehicle covering. This is particularly advantageous because the gas pressure in the gas distributing duct is particularly high initially and therefore easily opens or detaches the vehicle covering so that the air bag itself will then no longer require a large amount of force to emerge through the corresponding opening. The most important advantage is a shorter inflating time of the air bag so that it can have an earlier protective effect.
It is also preferred to provide fastening passage holes in the gas distributing duct and/or the air bag itself which are formed by welded connections, glued connections, sewn connections or woven connections and are sealed off with respect to the interior of the gas distributing duct or the air bag itself. Tension folds of the air bag can also be formed by welded connections, glued connections, sewn connections or woven connections. This facilitates the fastening of the air bag, in which case the corresponding fastening passage holes can be produced directly while establishing the welded connections, glued connections, sewn connections or woven connections for forming the gas distributing duct and the gas passage openings. Separate expenditures, therefore, are not required. The same applies to tension folds in the air bag which optimize its shape and inflating performance.
Within the scope of the manufacturing process of an air bag system according to the invention, a gas distributing duct is formed in an air bag by a welded, glued, sewn or woven connection of the air bag material, which gas distributing duct extends at least partially at an angle with respect to the main inflating direction of the air bag. Between the welded, glued, sewn or woven connections, gas passage openings are left. As a result, the above-mentioned air bag system or its air bag can be produced and the above-explained advantages are achieved.
Reference has also been made to the advantages provided during the manufacturing process of an air bag system when, simultaneously with the welded, glued, sewn or woven connections for forming the gas distributing duct, fastening passage holes and/or tension folds are formed. The fastening passage holes are sealed off with respect to the interior of the gas distributing duct and/or of the air bag, and the tension folds are formed by the welding-together, gluing-together, sewing-together or weaving-together of the air bag material.
The same applies to the further development of the manufacturing process according to which, before providing the welded, glued, sewn or woven connection, the air bag material is folded to form the gas distributing duct in order to have two or more layers in the area of the gas distributing duct.
For achieving the above-mentioned objects, the invention also provides a triggering process for an air bag system which contains an air bag accommodated behind a vehicle covering. In this process, gas is guided from a gas generator into a gas distributing duct made of air bag material situated behind the vehicle covering. The inflating gas distributing duct has already opened up the vehicle covering at least partially such that the air bag can emerge. The corresponding effects and advantages are described above.
A preferred further development of the triggering process is that the inflating gas distributing duct detaches the vehicle covering at least partially from the vehicle parts covered by it so that the air bag can emerge between the vehicle covering and the vehicle parts covered by it.
The invention also comprises a motor vehicle with at least one air bag system as mentioned above according to the invention. In such a motor vehicle, the air bag is mounted in a folded condition as a package optionally by covering and fastening devices on a vehicle covering of the motor vehicle. In addition or as an alternative, the air bag can be fastened in a folded-together condition as a package optionally by covering and fastening devices as well as fastening elements, together with the vehicle covering of the motor vehicle, on other parts of the motor vehicle.
As mentioned above, the vehicle covering is a prefabricated ceiling of the vehicle.
The advantages described above which occur when the air bag is mounted in a folded-together condition as a package, optionally by the covering and fastening devices on a vehicle part, apply to the whole claimed motor vehicle.
According to a further preferred embodiment of the invention, the vehicle part is a frame part of a sliding roof. In this case, the air bag or the air bag system may also be accommodated in a housing, for which, for example, the frame part of the sliding roof can be utilized.
According to preferred further developments, the frame part of the sliding roof is a side member which extends in the longitudinal direction of the vehicle and on which a side air bag is mounted, and/or the frame part of the sliding roof is a cross member which extends in the transverse direction of the vehicle. An air bag is mounted on the frame part for protection between occupants sitting in the front and the rear or for closing the sliding roof opening. In the latter version, the air bag for closing the sliding roof opening preferably has a T-shaped cross-section relative to the longitudinal direction of the vehicle so that the vertical part of the air bag is used for providing a protective cushion between occupants sitting in the left front and in the right front when the air bag system is triggered. Air bag slide rails can additionally or alternatively be provided along the sliding roof cover slide rails for the air bag for closing off the sliding roof opening, and guiding devices can be provided on the air bag for guiding this air bag in the air bag slide rails during triggering of the air bag system.
Finally, the invention contains an air bag system having a gas generator and an air bag, in which case the air bag, with or without a housing, can be mounted on a frame part of a sliding roof.
A further development of the above will be described in the context of the motor vehicle according to the invention. Specifically, the air bag is a side air bag and the frame part is a side member which extends in the longitudinal direction of the vehicle. The air bag may be an air bag for protection between sitting occupants in the front and in the rear or an air bag for closing the sliding roof opening. The frame part of the sliding roof may be a cross member which extends in the transverse direction of the vehicle. In a particular embodiment, the air bag for closing the sliding roof opening, in a condition installed in the vehicle and inflated, may have a T-shaped cross-section. The latter can be further developed by providing air bag slide rails and guiding devices on the air bag for guiding the air bag into the air bag slide rails during triggering of the air bag system. The air bag slide rails can be mounted at least essentially along sliding roof cover slide rails.
The two German Patent Applications mentioned above (DE 196 04 055.8 and DE 196 32 222.7), also by the present applicant, relate to an inside lining for a vehicle roof for accommodating roof air bag systems. In this respect, as well as with respect to the objects of European Patent Document EP 97 102 307.2 and of German Patent Document DE 196 42 964.1, the present invention provides further improvements and advantageous supplementations and alternatives. To the extent that characteristics from the older applications mentioned above can be combined with the present invention, the contents of the two German Patent Applications DE 196 04 055.8 and DE 196 32 222.7 as well as of European Patent Document EP 97 102 307.2 and of German Patent Document DE 196 42 964.1 are incorporated completely in the present document by reference in order to avoid a direct complete repetition of their contents.